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Iron depletion is common in regular blood donors. The objective of the study was to investigate the frequency and severity of iron depletion in regular blood donors and whether IV iron is more effective than oral to avoid iron depletion and symptoms thereof, especially restless legs syndrome (RLS). One hundred and twenty blood donors with at least five previous whole blood donations were randomized to receive either IV iron sucrose (Venofer(®), RenaPharma/Vifor, Uppsala, Sweden), 200 mg, or to 20100 mg of oral iron sulphate (Duroferon(®), GlaxoSmithKline, Stockholm, Sweden), after each blood donation during 1 year. Iron status and RLS incidence and severity were investigated. Iron status was generally poor among regular blood donors, especially in women, with a high incidence of iron depletion (>20%) and RLS (18%). The IV iron group increased storage iron to a greater extent than the oral iron group after 12 months (P=00043). Female donors were more responsive to IV iron sucrose compared to oral iron sulphate, particularly female donors below 50 years of age. RLS severity scores were significantly lower in the IV iron group. The two treatments were safe. Iron status is poor in regular blood donors, restless legs syndrome is common, and the routine iron supplementation is insufficient. IV iron sucrose substitutes iron loss in blood donors more efficiently compared with oral iron sulphate, especially in women. Iron substitution to blood donors should be individualized and based on P-ferritin monitoring.

Which deficiency is the cause of restless leg syndrome?